One invention herein is directed to treating patients having pathological conditions involving proliferation of pathologic microbes or pathologic helminths or pathologically proliferating mammalian cells. Another invention herein is directed to treating patients in need of increased nitrosative stress defenses.
Nitric oxide (NO) is now recognized as a signaling molecule in biology and has been implicated in the function of virtually every organ system in mammals. It is known that NO relaxes blood vessels, intestines, airways and skeletal muscles and plays a role in memory, sexual behavior and host defense. On the other hand, excessive production of NO has been implicated in organ dysfunction, degenerative disease and promotion of cancer. Arthritis, ulcerative colitis, Alzheimer""s disease, congestive heart failure, septic shock and atherosclerosis are disorders in which NO may play a pathogenic role.
It is recognized that there is normally a certain amount of endogenously produced oxidative stress in mammals, i.e., the endogenous production of reactive oxygen species in the body, e.g., superoxide, hydrogen peroxide, hydroxyl radical, hypochlorous acid and singlet oxygen. This is thought to contribute to ageing, rheumatism, atherosclerosis, inflammation, respiratory distress syndrome, fibrosis, and development of infectious diseases such as AIDS.
Before the discovery leading to the inventions herein, it was not recognized that there is a nitrosative stress distinct from oxidative stress that affects mammals and also microorganisms which can be manipulated in a therapeutically effective manner, either by decreasing microbial, helminth or pathologically proliferating mammalian cell defenses against nitrosative stress or by imposing a nitrosative stress or by upregulating nitrosative stress defenses.
We turn firstly to the inventions herein related to manipulating nitrosative stress to kill or reduce the growth of pathologic microbes or pathologic helminths or pathologically proliferating mammalian cells.
It has been discovered that cells producing or exposed to nitric oxide related compounds as defined below are subjected to nitrosative stress.
The term xe2x80x9cnitric oxide related compounds is used herein to mean compounds able to transfer NO+, NOxe2x88x92 or NO2+ group to biological molecules. The term does not include nitric oxide itself. Nitric oxide itself is not a nitrosative stress agent.
The term xe2x80x9cnitrosative stressxe2x80x9d is used herein to mean an impetus for NO or NO2 group attachment to proteins, nucleic acids or other biological molecules. It may be potentially therapeutic if microbes, helminths or pathologically proliferating mammalian cells are affected or potentially pathologic if normal mammalian cells are damaged. Nitrosative stress is distinct from oxidative stress and can occur under anaerobic conditions.
It has further been discovered that to prevent damage from nitrosative stress, cells exhibit constitutive defenses as well as an adaptive response that applies to microorganisms including bacteria as well as to helminths and to mammalian cells including human cells. An important aspect of this adaptive response is that it is distinct in its regulation and in its molecular purpose from the adaptive response to oxidative stress. Specifically, it has been discovered that cells upregulate resistance genes and other biochemical pathways to protect themselves from nitrosative stress. Thiols (e.g., glutathione in mammals and glutathione-producing helminths and microorganisms, L-homocysteine, mycothiol, ovothiols, etc.) and enzymes which mediate constitutive thiol synthesis comprise the first line of defense. Antinitrosative stress genes and their products comprise a second line of defense.
The term xe2x80x9cantinitrosative stress genexe2x80x9d is used herein to mean a gene coding for a product that when expressed either breaks down or eliminates nitrosants (nitrosating species), denitrosates nitrosatively inhibited proteins or other biological molecules to restore their function, or upregulates other products or pathways which are protective against nitrosative stress.
An embodiment of the invention herein involves selective manipulation of nitrosative stress so that it selectively affects pathologic microbe proliferation or survival or pathologic helminth proliferation or survival or pathologic cell proliferation, growth or survival in mammals (including humans). This manipulation of nitrosative stress can be in microbes infecting the mammals or in mammalian cells infected with pathologic microbes to selectively kill or inhibit the microbes or the host cells containing the microbes or in pathologic helminths infecting the mammal to selectively kill or inhibit the helminths or in pathologically proliferating mammalian cells, e.g., to selectively kill target cells (e.g., proliferating cancer cells or cells proliferating to cause restenosis or benign prostatic hypertrophy). The invention of this embodiment is a method of inhibiting growth of pathologic microbes or pathologic helminths or pathologically proliferating mammalian cells, in a mammal, and comprises administering to said mammal a therapeutic pathologic microbe or pathologic helminth or pathologically proliferating mammalian cell antiproliferative effective amount of one or more manipulators of nitrosative stress in said microbes or in mammalian host cells infected with said microbes or in said helminths or in said pathologically proliferating cells whereby nitrosative stress selectively kills or reduces the growth of said microbes or helminths or mammalian cells or selectively enhances their susceptibility to innate immune defenses or the susceptibility of said microbes to antimicrobial agents (that function by a mechanism other than by manipulating nitrosative stress) or the susceptibility of said helminths to anthelmintic agents (which function by a mechanism other than by manipulating nitrosative stress) or the susceptibility of said pathologically proliferating mammalian cells to antiproliferation agents (that function by a mechanism other than by manipulating nitrosative stress); provided that when the pathologically proliferating mammalian cells are those that would cause restenosis, the manipulator(s) of nitrosative stress comprise(s) an inhibitor of protection against nitrosative stress and is (are) employed to selectively kill or reduce the growth of said cells or to enhance their susceptibility to antiproliferation agents, i.e., to anti-restenosis drugs that function by a mechanism other than by manipulating nitrosative stress.
The terms xe2x80x9cpathologic microbesxe2x80x9d and xe2x80x9cpathologic microorganismsxe2x80x9d as used herein mean pathologic microorganisms including but not limited to pathologic bacteria, pathologic viruses, pathologic Chlamydia, pathologic protozoa, pathologic Rickettsia, pathologic fungi, and pathologic mycoplasmata.
The term xe2x80x9chost cells infected with pathologic microbesxe2x80x9d includes not only mammalian cells infected with pathologic viruses but also mammalian cells containing intracellular bacteria or protozoa, e.g., macrophages containing Mycobacterium tuberculosis, Mycobacterium leper (leprosy), or Salmonella typhi (typhoid fever).
The term xe2x80x9cpathologic helminthsxe2x80x9d as used herein refers to pathologic nematodes, pathologic trematodes and pathologic cestodes.
The term xe2x80x9cpathologically proliferating mammalian cellsxe2x80x9d as used herein means cells of the mammal that grow in size or number in said mammal so as to cause a deleterious effect in the mammal or its organs.
The term xe2x80x9cselectively kills or reduces the growth of said microbes or helminths or mammalian cellsxe2x80x9d as used herein means kills or reduces growth of pathologic microbes or host cells containing pathologic microbes or pathologic helminths or pathologically proliferating mammalian cells without causing unacceptable killing or inhibition of growth of normal mammalian cells or kills or reduces growth of mammalian host cells containing pathologic microbes or pathologically proliferating mammalian cells in a percentage which is at least 10% greater than the percentage of normal mammalian cells adversely affected.
The term xe2x80x9ctherapeutic pathologic microbe or pathologic helminth or pathologically proliferating mammalian cell antiproliferative effective amountxe2x80x9d as used herein means amount causing reduction in rate of proliferation of at least 10%.
The term xe2x80x9cantiproliferative agentxe2x80x9d is used herein to mean anticancer agent useful to inhibit growth of pathologically proliferating cancer cells or anti-restenosis drug useful to inhibit growth of pathologically proliferating cells that would cause restenosis or drug used to inhibit growth of pathologically proliferating cells causing benign prostatic hypertrophy or drug inhibiting growth of other kinds of pathologically proliferating cells, that does not function by manipulating nitrosative stress.
So far as microbes are concerned, the method is for inhibiting growth of pathologic microbes in a mammal and said method comprises administering to said mammal a therapeutic pathologic microbe antiproliferative effective amount of one or more manipulators of nitrosative stress in said microbes or in host cells infected with said microbes whereby nitrosative stress selectively kills or reduces the growth of said microbes or enhances their susceptibility to innate immune defenses or their susceptibility to antimicrobial agents. In a narrow embodiment herein where the microbes are protozoa, the manipulator of nitrosative stress administered is one that increases nitrosative stress in the pathologic microbes, or a manipulator of nitrosative stress administered is one that selectively inhibits protection against nitrosative stress in the pathologic protozoa but does not increase nitrosative stress in the pathologic protozoa and other manipulator of nitrosative stress is also administered which increases nitrosative stress in the pathologic protozoa, or a manipulator of nitrosative stress is administered which is a selective inhibitor of thiol synthesis by the protozoa. In a narrow embodiment herein where manipulator of nitrosative stress is administered which inhibits OxyR transcription or translation in microbes containing OxyR, manipulator of nitrosative stress is also administered which increases nitrosative stress in the pathologic microbes containing OxyR or which inhibits protection against nitrosative stress in said microbes in a way other than by inhibiting OxyR transcription or translation.
So far as helminths are concerned, the method is for inhibiting the growth of pathologic helminths in a mammal and said method comprises administering to said mammal a therapeutic pathologic helminth antiproliferative effective amount of a manipulator of nitrosative stress in said helminths whereby nitrosative stress selectively kills or reduces the growth of said helminths or enhances their susceptibility to innate immune defenses or their susceptibility to anthelmintic agents.
So far as pathologically proliferating mammalian cells are concerned, the method is for inhibiting the growth of pathologically proliferating mammalian cells in a mammal and comprises administering to said mammal a therapeutic pathologically proliferating mammalian cell antiproliferative effective amount of one or more manipulators of nitrosative stress in said cells whereby nitrosative stress selectively kills or reduces the growth of said cells or enhances their susceptibility to innate immune defenses or enhances their susceptibility to antiproliferation agents; except that when the pathologically proliferating mammalian cells are those that would cause restenosis, the manipulator(s) of nitrosative stress comprise(s) an inhibitor of protection against nitrosative stress (e.g., one or more inhibitors of protection against nitrosative stress are used as the only kind of manipulator of nitrosative stress or two kinds of manipulators of nitrosative stress are employed where one kind of manipulator of nitrosative stress is inhibitor of protection against nitrosative stress and the other kind of manipulator of nitrosative stress is agent which increases nitrosative stress) and is (are) employed to selectively kill or reduce the growth of said cells or to enhance their susceptibility to antiproliferation agents, i.e., to anti-restenosis drugs that function by a mechanism other than by manipulating nitrosative stress.
We turn now to special cases mentioned above.
It is known in the prior art to inhibit growth of protozoa by inhibiting thiol synthesis therein. In this regard, see Arrick, B. A., Griffith, O. W., and Cerami, A. J., Exp. Med. 153, 720-725 (1981). However, the mechanism for growth inhibition of protozoa of inhibiting protection against nitrosative stress has not heretofore been known, and administration of microbe selective thiol production inhibiting agents to mammals to inhibit growth of protozoa therein is not exemplified in the prior art. Moreover, it is not known in the prior art to inhibit growth of protozoa in mammals by therapeutic administration to increase nitrosative stress therein. Furthermore, it is not known in the prior art to combine increased nitrosative stress with thiol depletion or other strategies for decreasing defenses against nitrosative stress, for inhibiting growth of protozoa in mammals.
It is known in the prior art that OxyR protects bacteria from oxidative stress but the role of OxyR in providing protection against nitrosative stress has not heretofore been known. In this regard, see Papp-Szabo, B., et al., Infection and Immunity 62, 2662-2668 (1994). Moreover, it is not known in the prior art to administer inhibitor of OxyR transcription or translation to mammals to inhibit growth of bacteria therein, and it is not known in the prior art to inhibit growth of or to kill bacteria by therapeutically increasing nitrosative stress therein.
It is known in the prior art to insert NO releasing stents during angioplasty. However, it is not known in the prior art to administer manipulator of nitrosative stress which inhibits protection against nitrosative stress to selectively kill or reduce the growth of pathologically proliferating cells that would cause restenosis or to selectively enhance their susceptibility to antiproliferation agents that function by a mechanism other than by manipulating nitrosative stress. Moreover, it is not known in the prior art to concurrently administer manipulator of nitrosative stress which increases nitrosative stress and manipulator of nitrosative stress which inhibits protection against nitrosative stress in the pathologically proliferating cells that would cause restenosis.
We turn now to various kinds of manipulators of nitrosative stress.
One kind of manipulator of nitrosative stress is a selective inhibitor of protection against nitrosative stress in the pathologic microbes or in host cells infected with pathologic microbes or in the pathologic helminths or in the pathologically proliferating mammalian cells. The term xe2x80x9cselective inhibitorxe2x80x9d is used in the prior sentence to refer to agent which in use downregulates nitrosative stress defense mechanism in the pathologic microbes or in mammalian host cells infected with pathologic microbes or in pathologic helminths or in pathologically proliferating mammalian cells so as to effect or mediate the selective killing or growth reduction recited above.
One kind of selective inhibitor of protection against nitrosative stress is a selective inhibitor of thiol synthesis or selective depleter of thiol in the pathologic microbes or in mammalian host cells infected with pathologic microbes or in pathologic helminths or in pathologically proliferating mammalian cells. The term xe2x80x9cselective inhibitor of thiol synthesisxe2x80x9d as used herein refers to synthesis from amino acids or other precursors and means a selective inhibition of a distinct enzyme present in the pathologic microbes or in the pathologic helminths (i.e., a microbe-selective or helminth selective thiol synthesis inhibiting agent) or to selective application or action of an inhibitor of thiol synthesis which is itself not selective for inhibition of thiol synthesis in pathologically proliferating microbes or helminths or mammalian cells but which achieves selective result because of coaction with drug that has more specific application or action or by virtue of local delivery. The term xe2x80x9cselective depleter of thiolxe2x80x9d as used herein means agents which conjugate with thiols; agents transferring nitroso (xe2x80x94NO) or nitro (xe2x80x94NO2) groups to thiols which, when administered systemically to the mammal, are selective for pathologic microbes infecting the mammal, host cells containing pathologic microbes, pathologic helminths infecting the mammal or pathologically proliferating mammalian cells; alkylating agents administered systemically to a mammal to inhibit growth of pathologic microbes in the mammal infected with the microbes or to inhibit growth of pathologic helminths in the mammal infected with the helminths; depleters of thiol that are administered locally; and prodrugs for agents causing thiol depletion, which are activated in pathologic microbes or in pathologic microbe-infected cells or in pathologic helminths. The term xe2x80x9cselective depleter of thiolxe2x80x9d as used herein excludes the systemic administration of alkylating agents to mammals to inhibit growth of pathologically proliferating mammalian cells, the systemic administration of agents which cause thiol oxidation to disulfides and the systemic administration of thiol reductase (e.g., glutathione reductase also known as glutathione disulfide reductase) inhibitors, except when these agents or inhibitors are used with agents that increase nitrosative stress.
Another kind of selective inhibitor of protection against nitrosative stress is a selective inhibitor of transcription or translation of an antinitrosative stress gene (as defined above) or a selective inhibitor of an antinitrosative stress gene product. OxyR is a transcription factor in E. coli and Salmonella which has been discovered by us to be upregulated by nitrosative stress as described in Hausladen, A., et al., Cell, Vol. 86, pages 11-20 (1996). As indicated above, in a narrow embodiment herein where manipulator of nitrosative stress is administered which inhibits the transcription factor OxyR in microbes containing it, manipulator of nitrosative stress is also administered which inhibits protection against nitrosative stress in the microbes in a way other than by inhibiting OxyR transcription or translation or which increases nitrosative stress, e.g., two kinds of manipulators of nitrosative stress are administered and one kind inhibits OxyR transcription or translation and the other kind selectively inhibits thiol synthesis or depletes thiol in the microbe or increases nitrosative stress in the microbe.
Another kind of manipulator of nitrosative stress useful in the method described above is an agent that selectively increases nitrosative stress in the pathologic microbes or in the pathologic helminths or in the pathologically proliferating mammalian cells. The term xe2x80x9cagent that increases nitrosative stressxe2x80x9d refers to an agent that imposes nitrosative stress and includes nitrosating agent, that is agent that transfers NO+, NOxe2x88x92 or NO2+ group, or prodrug causing this effect, or an agent that activates or induces nitric oxide synthase or nitrogen oxide producing enzyme where nitrogen oxide is in part converted to nitric oxide related compounds. In one embodiment herein, the manipulator of nitrosative stress is not agent that activates or induces mammalian nitric oxide synthase or other nitrogen oxide producing enzyme and nitrosative stress is not imposed by conversion of nitrogen oxide to nitric oxide related compounds in the body.
In one aspect of the invention, the inhibition is carried out on pathologic microbes or pathologic helminths and the manipulator of nitrosative stress is one that selectively delivers nitrosating agent to the pathologic microbes or to host cells containing the pathologic microbes or to the pathologic helminths, i.e., agent that transfers NO+, NOxe2x88x92 or NO2+ group to the pathologic microbes or to the pathologic helminths. This type of manipulator of nitrosative stress can be an organic or inorganic nitrate or nitrite that selectively delivers nitrosating agent to the microbes or helminths. Such manipulator of nitrosative stress can be selected from the group consisting of substrates for nitrite reductase or nitrate reductase and nitrogen-oxide substrates for microbial sulfite metabolizing enzymes. Another example of manipulator of nitrosative stress that selectively delivers nitrosating agent to the pathologic microbes or to host cells containing them or to the pathologic helminths is antibiotic or drug that kills or reduces growth of said microbes (including antiviral compounds) or helminths, substituted to transfer NO+, NOxe2x88x92 or NO2+ group, to the microbes or helminths.
In another aspect of the invention herein two kinds of manipulators of nitrosative stress in said microbes or in mammalian host cells infected with said microbes or in said helminths, or in said pathologically proliferating mammalian cells are employed and one kind is a selective inhibitor of protection against nitrosative stress in said microbes or in said host cells or in said helminths or in said pathologically proliferating mammalian cells, and the other kind is a selective increaser of nitrosative stress in said microbes or host cells or helminths or pathologically proliferating mammalian cells, or prodrug therefor, and either the inhibition of protection against nitrosative stress or the increase of nitrosative stress or both are selectively effected in said microbes or host cells or helminths or mammalian cells.
In still another aspect of the invention, a single agent is employed as the manipulator of nitrosative stress, which both inhibits protection against nitrosative stress and also causes increase of nitrosative stress in the pathologic microbes or in mammalian host cells infected with said microbes, or in the pathologic helminths or in the pathologically proliferating mammalian cells.
Specific applications of general methods described above include selectively killing or reducing growth of pathologic microbes, e.g., bacteria, infecting a mammal, selectively killing or reducing growth of pathologic helminths in a mammal, selectively killing or reducing growth of pathologically proliferating cancer cells in a mammal, selectively inhibiting the cell proliferation or enlargement that would cause restenosis (e.g., by administering the manipulator fastened to a stent), and selectively inhibiting the cell proliferation or enlargement that would cause benign prostatic hypertrophy (e.g., by local administration of the manipulator).
We turn now to the application of selectively killing or reducing the growth of pathologically proliferating cancer cells in a mammal.
A preferred agent administered to mammals with pathologically proliferating cancer cells to kill or reduce growth of cancer cells in the mammal is a chemotherapeutic agent which transfers or which has been derivatized to transfer NO+, NOxe2x88x92 or NO2+ group to said cells. For example, where the cancer cells are of a type which may be treated by administration of an alkylating agent, the manipulator of nitrosative stress is an alkylating agent which transfers NO+, NOxe2x88x92 or NO2+ group to the cancer cells or which has been derivatized to transfer NO+, NOxe2x88x92 or NO2+ group to the cancer cells. For example, where the pathologically proliferating cancer cells are of a type which may be treated by administration of melphalan, the manipulator of nitrosative stress may be melphalan derivatized to transfer NO+, NOxe2x88x92 or NO2+ group to the cancer cells being treated. In an embodiment herein, the agent administered to mammals with pathologically proliferating cancer cells is not agent with polymer bound nitric oxide releasing N2O2xe2x88x92 functional groups.
In a preferred method directed to the application of killing or reducing growth of pathologically proliferating cancer cells in a mammal, two kinds of manipulators of nitrosative stress are administered to the mammal affected with cancer, and one kind is an inhibitor of protection against nitrosative stress and the other kind is an agent that increases nitrosative stress and very preferably one or both of these two kinds of manipulators of nitrosative stress are selective for this(these) effect(s) in the cancer cells.
We turn now to the application of selectively inhibiting the cell proliferation that would cause restenosis. The method herein is preferably carried out by fastening one or a plurality of kinds of the manipulators of nitrosative stress to a stent inserted during angioplasty. This provides local application of the manipulator(s) of nitrosative stress to pathologically proliferating cells that would cause restenosis. In an embodiment of the invention herein, a single agent or a plurality of agents are attached to a stent to perform both the function of inhibiting glutathione synthesis in the pathologically proliferating cells and the function of increasing nitrosative stress in the pathologically proliferating cells. In one example of this method, inhibitor of thiol synthesis or depleter of thiol is attached to and administered from a stent as the sole manipulator of nitrosative stress and the insertion of the stent with inhibitor of thiol synthesis or depleter of thiol thereon is optionally followed by administration of intravascular beta-, gamma- or X-ray radiation. In a preferred method herein two kinds of manipulators of nitrosative stress are administered and both are associated with a porous polymer coated on a stent whereby the two kinds of manipulators of nitrosative stress leach out of the porous polymer and contact the pathologically proliferating cells and one kind of manipulator of nitrosative stress is L-buthionine-S-sulfoximine and the other kind of manipulator of nitrosative stress is an agent that increases nitrosative stress or NO-substituted L-buthionine-S-sulfoximine is administered by being associated with a porous polymer coated on a stent. In other alternatives, L-buthionine-S-sulfoximine is fastened to and administered from a stent and agent that increases nitrosative stress is administered systemically or agent that increases nitrosative stress is attached to and administered from a stent and L-buthionine-S-sulfoximine is administered systemically.
We turn now the application of selectively inhibiting the cell proliferation that would cause benign prostatic hypertrophy. Methods herein for this application comprise local injection into the prostate of an agent that inhibits glutathione synthesis or depletes glutathione or the implantation in the prostate of a pellet associated with said agent or the systemic administration of glutathione synthesis inhibiting or depleting agent with co-administration of drug which does not manipulate nitrosative stress. that inhibits benign prostatic hypertrophy or the systemic administration of conventional drug for treatment of benign prostate hypertrophy which has been NO-substituted.
Another embodiment herein is directed to treating infections of the oral cavity in a mammal comprising topically administering to the site of the infection, an infection reducing effective amount of a manipulator of nitrosative stress in the infection-causing organism, especially an S-nitrosothiol.
Another embodiment herein is directed to treating infected skin lesions in a mammal comprising topically administering to the skin lesions an infection reducing effective amount of S-nitrosothiol applied as S-nitrosothiol or which can be formed in situ from and after administration to the lesions of a mixture comprising inorganic nitrite, pharmacologically acceptable acid and thiol.
Another embodiment herein is directed to treating protozoal infections in a mammal and comprises systemically administering to said mammal an infection reducing amount of L-buthionine-S-sulfoximine and agent that increases nitrosative stress.
In another embodiment, an agent which increases oxidative stress is administered to mammal infected with a pathologic microbe or a pathologic helminth or afflicted with pathologically proliferating mammalian cells, concurrently with the manipulator of nitrosative stress, and the combination of said agent and said manipulator selectively kills or reduces the growth of the pathologic microbes or of the pathologic helminths or enhances their susceptibility to innate immune defenses or the susceptibility of said microbes to antimicrobial agents (which function by a mechanism other than by increasing oxidative stress or by manipulating nitrosative stress) or the susceptibility of said helminths to anthelmintic agents (which function by a mechanism other than by increasing oxidative stress or by manipulating nitrosative stress) or selectively kills or reduces the growth of the pathologically proliferating mammalian cells or enhances their susceptibility to innate immune defenses or to antiproliferation agents (which function by a mechanism other than by increasing oxidative stress or by manipulating nitrosative stress).
Another embodiment herein is directed to a method for inhibiting growth of pathologic microbes in a mammal (including humans), comprising administering to said mammal a therapeutic pathologic microbe antiproliferative effective amount of a metal chelating agent and of an agent that increases nitrosative stress.
Another embodiment herein is directed to a method of inhibiting growth of pathologic microbes or pathologic helminths or pathologically proliferating mammalian cells in a mammal comprising administering to said mammal a therapeutic pathologic microbe or pathologic helminth or pathologically proliferating mammalian cell antiproliferative effective amount of agent that converts endogenously produced NO in the microbe, helminth and/or mammal to nitric oxide related compound or to NO+ or NOxe2x88x92, especially redox active metal catalysts, preferably with administration of agent that causes increased NO production in the microbe, helminth and/or mammal, e.g., a cytokine to increase NO production in the mammal.
Another embodiment herein is directed to a method of inhibiting growth of pathologically proliferating mammalian cells, in a mammal (including humans), or for killing or reducing the growth of mammalian host cells infected with pathologic microbes, comprising administering to said mammal a therapeutic pathologically proliferating mammalian cell or pathologic microbe antiproliferative effective amount of a blocker of the ability of the cells to export nitrosant and of an agent that increases nitrosative stress in the cells. The term xe2x80x9cnitrosantxe2x80x9d is used here to mean an agent or endogenous species able to deliver NO+, NOxe2x88x92 or NO2+ group to biological molecules.
Another embodiment herein is directed to a method of inhibiting growth of pathologic microbes or of pathologic helminths or of pathologically proliferating mammalian cells, in a mammal, said method comprising administering to said mammal a pathologic microbe or pathologic helminth or pathologically proliferating mammalian cell antiproliferative effective amount of agent that increases nitrosative stress in said pathologic microbes or in host cells infected with said pathologic microbes or in said pathologic helminths or in said pathologically proliferating mammalian cells whereby nitrosative stress selectively kills or reduces the growth of said microbes or said helminths or said pathologically proliferating mammalian cells or selectively enhances their susceptibility to innate immune defenses or the susceptibility of said microbes to antimicrobial agents (which function by a mechanism other than by manipulating nitrosative stress) or the susceptibility of said helminths to anthelmintic agents (which function by a mechanism other than by manipulating nitrosative stress) or the susceptibility of the pathologically proliferating mammalian cells to antiproliferative agents (which function by a mechanism other than by manipulating nitrosative stress), and also administering to said mammal a hypotensive response preventing or reducing amount of an inhibitor of guanylyl cyclase.
An embodiment of the invention here overlapping some of the embodiments described above and broader than these embodiments in certain respects is a method of inhibiting growth of non-viral pathologic microbes in a mammal (including humans), said method comprising administering to said mammal a pathologic microbe antiproliferative effective amount of a selective inhibitor of thiol synthesis in the microbe to mediate selective killing or growth reduction of said pathologic microbes by agent which is selected from the group consisting of antimicrobials (which are not selective inhibitors of thiol synthesis in the microbe), immune cells in the mammal and products of mammalian antimicrobial response.
Another aspect of the invention is directed to a method of inhibiting growth of pathologic viruses in a mammal (including humans), said method comprising administering to the mammal a non-selective glutathione synthesis inhibitor or glutathione depleter which causes decrease in amount of glutathione in the host cells for the virus and thereby sensitizes the virus to selective killing by antiviral agent, immune cells in the mammal and products of the mammalian antiviral response.
In another embodiment herein, hydroxyurea is administered together with a non-selective glutathione synthesis inhibitor or depleter, e.g., L-buthionine-S-sulfoximine, to treat those disorders now being treated with hydroxyurea without glutathione synthesis inhibitor or depleter.
Another aspect of the invention herein is directed to novel sulfoximines which selectively inhibit glutathione synthesis in glutathione producing microbes, e.g., E. coli and Salmonella, when administered to an infected mammal, because they strongly inhibit glutathione synthesis in the glutathione producing microbes but not in mammalian cells. These novel sulfoximines are xcex1-alkyl-S-alkyl-homocysteine sulfoximines wherein the xcex1-alkyl contains 2 to 8 carbon atoms and the S-alkyl contains 1 to 10 carbon atoms. some examples of species of this genus are xcex1-ethyl-buthionine sulfoximine, xcex1-propyl-buthionine sulfoximine, xcex1-isopropyl-buthionine sulfoximine, and xcex1-tert butyl-buthionine sulfoximine.
We turn now to the invention herein related to treating patients in need of increased nitrosative stress defenses. This can involve manipulating nitrosative stress in a patient to upregulate nitrosative stress defense mechanism in the patient.
One embodiment of this involves a method of treating a mammal in need of increased nitrosative stress defenses and comprises administering to said mammal a nitrosative stress tolerance increasing amount of a manipulator of nitrosative stress to cause increase of nitrosative stress defense mechanism in the mammal.
Another embodiment of this involves a method of treating a mammal, e.g., a human patient, at risk for a cerebral stroke because of having had a transient ischemic attack or a prior stroke comprising upregulating nitrosative stress defense mechanism in said mammal thereby to protect neuronal cells from death from more severe nitrosative stress occurring in the event a cerebral stroke occurs in the mammal.